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New images of close-passing 2015 TB145

New, more detailed images and video – released yesterday – of object 2015 TB145, which swept close to Earth on Halloween. Does it still look like a skull?

The video at the top of this page, and the first two images below, are the latest radar releases showing 2015 TB145, which swept within 1.3 lunar distances of Earth on October 31, 2015, Halloween in North America. The object passed Earth at a distance of about 302,000 miles (486,000 km). As it passed, it was found to be spherical in shape and approximately 2,000 feet (600 meters) in diameter. It completes a rotation about once every five hours. Observations made last week by scientists using NASA’s Infrared Telescope Facility in Hawaii indicated the object was a comet, an icy body that had likely shed its volatiles after numerous passes around the sun. Meanwhile, in a statement from yesterday (November 3, 2015), NASA’s Jet Propulsion Laboratory continued to refer to the object as an asteroid.

View larger. | Newly released radar images of 2015 TB145. These 8 individual images were collected over a span of slightly more than an hour on October 31, when the asteroid was between 440,000 miles (710,000 km) and about 430,000 miles (690,000 km) distant. An antenna at Goldstone, California, was used to transmit high power microwaves toward the asteroid. The signal bounced off the asteroid, and their radar echoes were received by the National Radio Astronomy Observatory’s Green Bank Telescope in West Virginia. Image via NASA/JPL-Caltech/GSSR/NRAO/AUI/NSF.

A closeup, from the series of images above.

We had a lot of questions about the image of 2015 TB145 just below, which appears to show the object in the shape of a skull. As you can see from these more recent images, 2015 TB145 isn’t as skull-like as that earlier image suggested. The skull appearance of the object was a case of what’s called pareidolia, that is, seeing a familiar pattern of something that isn’t really there. It’s similar to a photo by Peter Lowenstein featured yesterday in our Today’s Image area, showing a cloud that looks like a barking dog. You can see many more examples of pareidolia on this page.

The images below are also 2015 TB145, acquired by both professional and amateur astronomers late last week as the object swept past Earth.

Boo! This image of the close-passing object on Halloween, 2015, clearly looks like a skull! It was generated using radar data collected by the National Science Foundation’s 1,000-foot (305-meter) Arecibo Observatory in Puerto Rico. The radar image was taken on October 30, 2015. Image resolution is 25 feet (7.5 meters) per pixel. Does this object really look like a skull? Well … Arecibo must have collected many, many images of this object. This is the one that looks most like a skull, released by them on this date, no doubt, because of the comet’s sweep past on Halloween. Image via NAIC-Arecibo/NSF.

View larger. | A series of radar images via the Arecibo telescope in Puerto Rico.

Here’s a closer look at one of the Arecibo radar images, above.

View larger. | 2015 TB145 captured using a 12″ S/C telescope and a Santa Barbara ST402ME camera, by Efrain Morales of the Astronomical Society of the Caribbean (SAC). Efrain’s images, combined to create this animation, show a lapse of 20 minutes. Images taken on October 30, 2015 at 0602 UTC from Aguadilla, Puerto Rico.

Gianluca Masi of the Virtual Telescope project dropped us an email with word of this wonderful sequence. The comet (asteroid … they’re only labels, after all) is the apparently still dot in the center. Really, it’s moving in front of the stars. Gianluca wrote: “A total of 276 frames taken back to back and covering 2h and 45 minutes. To our knowledge, no one did something similar with this target. Considering that 165 minutes of coverage are compressed in almost 14 seconds, the motion of the asteroid in the video is accelerated by a factor of 700x.” Thank you, Gianluca!

Scott MacNeill wrote: “Here is an animation I made from my shots of Asteroid 2015 TB145 approaching on Halloween morning. I captured these shots at Frosty Drew Observatory in Charlestown, Rhode Island. This animation has 34 exposures. Enjoy!” Thanks, Scott!

Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.